Multi-stage compressor

ABSTRACT

A MULTI-STAGE COMPRESSOR WHEREIN A PLURALITY OF DISKS ARE MOUNTED ON A SHAFT, WITH EACH OF THE DISKS HAVING A PLURALITY OF TUBULAR SCOOPS, WHEREBY AIR IS COMPRESSED UPON ROTATION OF THE DISCS BY THE PULLING OF AIR THROUGH THE SCOOPS IN SUCCESSIVE STAGES OF COMPRESSION TO THEREBY PROVIDE A SIMPLIFIED LOW COST AIR COMPRESSOR.

Sept. 20, 1971 w. A. WALLACE 3,606,559

MULTI-STAGE COMPRESSOR Filed July 15, 1969 2 Sheets-Sheet 1 T- Z Z INVENTOR phone! Willow & Mtfllaewl A TTOR NE YS Se t. 20, 1971 w. A. WALLACE MULTI-STAGE COMPRESSOR 2 Sheets-Sheet 2 Filed July 15, 1969 lNl ENTOR new! W'Jm & MaMLawA ATTORNEYS Patented Sept. 20, 1971 3,606,569 MULTI-STAGE COMPRESSOR William A. Wallace, 2438 Lord Baronof, Anchorage, Alaska 99503 Filed July 15, 1969, Ser. No. 841,928 Int. Cl. F01d 1/02 US. Cl. 415-199 4 Claims ABSTRACT OF THE DISCLOSURE A multi-stage compressor wherein a plurality of disks are mounted on a shaft, with each of the disks having a plurality of tubular scoops, whereby air is compressed upon rotation of the discs by the pulling of air through the scoops in successive stages of compression to thereby provide a simplified low cost air compressor.

BACKGROUND OF THE INVENTION The field of this invention is air compressors.

Some effort to develop simplified low cost air compressors has been made in the past as evidenced by US. Patents Nos. 2,910,223; 3,146,939; and 3,289,923. However,the compressors of such patents Work on the principle of moving air from the center of a disk to its outer circumference by centrifugal force. By reason of such air movement, a substantial pressure drop occurs and the volume flow of air through the compressor is excessively restricted.

SUMMARY OF THE INVENTION BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view, partly in elevation, illustrating the preferred form of the multi-stage compressor of this invention; and

FIG. 2 is a plan view taken on line 22 of FIG. 1;

FIG. 3 is a sectional view taken on line 33 of FIG. 1; and

FIG. 4 is an enlarged detailed view of one of the air scoops in one of the plates of the compressor of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, the letter C designates generally the compressor of this invention which has a housing H within which is disposed a rotatable shaft 10 with a plurality of rotatable plates or discs P mounted thereon. As will be explained in detail, each of the plates has a plurality of radially and circularly disposed scoops S for scooping air from one side of each of the plates P and discharging it at an increased pressure on the other side thereof. The plurality of plates P provides for increases in air pressure in stages from one plate to the next, whereby air which is drawn in through one or more inlet openings or tubes 12 is discharged at a discharge outlet pipe 14 at a relatively high pressure. Between each of the plates P, there is disposed an air spoiler A which serves to break up rotational movements of air as it flows from each of the plates P and to cause it to flow substantially parallel to the axis of the shaft 10 for increased efiiciency of operation.

Considering the invention more in detail, the housing H includes a cylindrical shell or body 20 which has a lower end closure 21 and an upper end closure 22. The end closures 21 and 22 may be secured to the cylinder or body 20 by any suitable means such as retaining bolts 23, which preferably are removable so that the interior of the housing H may be exposed for access to the plates P and the other working parts within the housing H. The shaft 10 extends substantially vertically in the preferred form of the invention and it has an upper bearing 30 and a lower bearing 31 of any conventional construction for sup porting the shaft 10 for substantially fritcionless rotation. A cover 32 is disposed over the upper end of the shaft 10 and the bearing 30, but it is preferably mova'bly mounted by bolts 33 so that access to the bearing 30 is possible. Similarly, a bearing housing 34 is secured to the lower end closure 21 by bolts 35 so that it also may be removed as desired for access to the bearing 31.

The shaft 10 is rotatably driven by any suitable power means, such as the gears 36 and 37 which are driven through a shaft 38 connected to any suitable source of power (not shown), such as a gasoline or diesel engine. The shaft 38 is also suitably supported in bearings 39 and 40 or is otherwise supported in any conventional manner for rotation to drive the gear 37 to thus impart rotation to the gear 36 and the shaft 10. The gears 36 and 37 are preferably enclosed by a gear housing 41 which is mounted on a base 42 and such base 42 may also serve as the base for the entire compressor C. The width of the base 42 may be enlarged or the weight thereof may be increased to provide for stability of the entire compressor C, as compared to the size of the base 42 illustrated in FIG. 1. Also, the base 42 may be bolted or otherwise mounted on a foundation for increased stability of the entire structure.

The shaft 10 is preferably formed in sections 10a, 10b, 10c, 10d, and 102 of different diameters, with the diameters progressively increasing from the smallest diameter portion 10a to the largest diameter portion 102. The different diameter sections, 10a through 10'e, are provided for the assembly and mounting of the plates P thereon, and also for the facilitating of the removal of such plates should it become desirable or necessary. Thus, the lowermost plate P has an internal diameter 42 which corresponds with the diameter of the section 10d and is therefore larger than the diameters of the sections 10a, 10b and 10c. Therefore, the plate P is positioned on the shaft 10 first from the upper end of the shaft 10 and it passes downwardly until it hits a shoulder provided at the junction between the sections 10d and 10e. The internal diameter of the bore 43 of the second lowest plate P is approximately the same size as the diameter of the section so that it fits into position and is supported by the shoulder between the sections 100 and 10d. The plate P which is just below the top plate has an internal bore 44 with a diameter substantially equal to the diameter of the section b, and it is therefore supported on the shoulder between the sections 10b and 100. Similarly, the uppermost plate P has an internal bore which is of a diameter substantially equal to the diameter of the section 10a so that it is supported on the shoulder between the sections 10a and 10b. Retaining rings or collars 46, 47, 48 and 49 are threaded on the sections 1011, 10c, 10b and 10a, respectively, to retain the plates P in their supported position on the respective shoulders of the shaft 10. It will be appreciated that the various other ways of mounting the plates P may be provided, but the construtcion described above is preferred in view of its many advantages of assembly and disassembly.

In FIG. 4, a portion of one of the plates P is illustrated with one of the scoops S of the preferred construction. The scoop S is a tube formed of metal of other material which extends through an inclined hole or opening 50 in the plate P. The angle of inclination of the hole 50 and therefore of the tube forming the scoop S, may vary to vary the flow conditions, but in the preferred form of the invention, such angle of inclination is about 45 with respect to the longitudinal axis of the shaft 10, or with respect to the plane of the plate P in which it is mounted. Each of the scoops S is provided with end openings 51 and 52, and the openings 51 face in the direction of rotation of the plates P so as to scoop the air therein and cause it to discharge through the lower openings 52.

The end edge 51a of the circular opening 51 is disposed substantially parallel to the axis of the shaft 10 and substantially perpendicular to the face of the plate P. Such structure facilitates the scooping of the air into each of the scoops S during the rotation of the plates P. The circular edge 52a of the discharge opening 52 of each of the scoops S may similarly be formed approximately parallel to the axis of the shaft 10 and perpendicular to the plane of the plate P as shown in FIG. 4. The scoop S illustrated in FIG. 4 is shown as being welded at an annular weld 53 and another annular weld 54 to the plate P. The construction shown in FIG. 4 is thus a relatively simple construction for providing the scoops S at the proper angle for rela tively high efficiency in the scooping of air from one side of the plate P and discharging it to the other side of such plate P at an increased pressure. It should be noted that the plates P are preferably spaced progressively closer together from the uppermost plate P to the lowermost plate P to provide for the compression of the air as it moves from the first stage to the last stage in the housing H.

The scoops S are arranged on each plate in a plurality of circles which are shown in FIG. 3, partly schematically, and there are a multiplicity of the scoops S in each of the circles. The number of scoops S may be varied as desired for changing the characteristics of the compression of the particular compressor. The plates P are solid plates other than for the scoops S which extend therethrough, and they extend out to a point almost in contact with the inner surface of the housing body or shell 20, but they are free to rotate with respect to such housing H.

Between each of the plates P is a foraminous sheet or screen which serves as the air spoiler A. Each of the air spoilers A is suitably secured to the housing body or shell 20 by screws or any other suitable fastening means which extend through the housing shell 20 and into the air spoilers A. The air spoilers A are perferably large mesh screens such as generally referred to as hardware cloth wherein the size of the opening may vary from about one quarter of an inch to one inch so that air which is discharged from the plate P adjacent thereto is forced to flow through such holes or openings in the screen A in a substantially parallel flow to the axis of the shaft 10. This breaks up the rotational fiow of the air as it is discharged from the plates P and causes it to move towards the next plate P in a flow pattern which is substantially non-turbulent whereby greater efficiency and air compression is obtained than would be otherwise possible. The size of the opening in the screen or air spoiler A is great enough so that there is very little restriction or reduction in the air pressure as the air is rendered non-turbulent and substantially parallel to the axis 10 as it moves from one plate P to the other.

In the operation or use of the air compressor C of this invention, the air is drawn in through the inlets 12 by the rotation of the plates P which scoops the air through the plurality of scoops S in each of the plates P and increases the pressure of same from one plate P to the other so that there is a gradually increasing pressure from the uppermost plate P to the lowermost plate P as seen in FIG. 1. Thus, the pressure of the air dis charged through the outlet tube 14 is at an increased pressure. For example, with shaft 10 rotating at approximately 7200 rpm, approximiately 5400 cubic feet per minute of air moves through the compressor C and discharges at a pressure of about 200 lbs. per square inch. If the roation of the shaft 10 is reduced to, for example, 3600 rpm, the volume of air flowing through the compressor C is reduced to 2700 cubic feet per minute, but the pressure of the air delivered at the discharge opening 14 will still be approximately 200 lbs. per square inch. With this invention, the pressure may be varied by varying the number of stages which is accomplished by varying the number of plates P, or by varying the sizes of the scoops or jets S, or the number or arrangement of such scoops S.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials as well as in the details of the illustrated construction may be made without departing from the spirit of the invention.

What is claimed is:

1. An air compressor, comprising:

a housing having an air inlet at one end and an air outlet at the other end;

a rotatable shaft extending longitudinally through the central portion of said housing;

bearing means for supporting each end of said shaft;

a plurality of solid rotatable plates secured to said shaft at longitudinally spaced intervals for rotation with said shaft;

air spoiler means between each pair of said plates for directing air in a direction substantially parallel to the axis of said shaft for breaking up rotational movement of air discharging between the plates;

power means for rotating said shaft and said plates thereon; and

each of said plates having a plurality of tubular scoops extending through said solid rotatable plate and which are radially and circularly disposed with respect to each other for scooping air from one side of each plate and discharging it at an increased pressure on the other side thereof;

each of said tubular scoops being a tube which is inclined with respect to the plane of the plate in which it is mounted and which has end openings on each side of said plate; and

each scoop having one of its end openings facing in the direction of rotation of said plates.

2. The structure set forth in claim 1, wherein:

the face of each of said end openings is substantially perpendicular to the plane of said plate.

3. The structure set forth in claim 1, wherein the angle of inclination of each of said tubes is about forty-five degrees relative to the axis of said shaft.

5 6 4. The structure set forth in claim '1, wherein each 3,224,667 12/1965 Strike et a1. 415199 of said air spoiler means is a foraminous disk having 3,250,458 5/1966 Caldwell 415199 openings which provide for substantially unrestricted flow of air therethrough. FOREIGN PATENTS 5 1,019,272 2/1966 Great Britain 416231 References Cited 1,019,497 2/1966 Great Britain 4l623'1 UNITED STATES PATENTS CORNELIUS J. HUSAR, Primary Examiner 1,793,179 2/1931 Lanterrnan et a1. 415-87 U.S.Cl.X.R.

3,146,939 9/1964 Schlumbohm 415 90 10 416229 

